* Implement `find_af_inet` which retrieves network interfaces which
belongs to either of both AF_INET or AF_INET6

* Implement `find_ifa` which find a network interface with a specific
name in a vector of network interfaces

Fixes

* Reimplement approach using `getifaddrs` instead of relying on stdout
from command execution

* Use different network interface names for "macos" and "linux" instead
of relying on "en0" for all os from the "unix" family